Expanding device for boiler tubes and the like



Nov. 13 1923. 11,4'73fi84 P. SLESAZECK EXPANDING DEVICE FOR BOILER TUBESAND THE LIKE Filed April 15. 1922 lnvenfor: finals/0.941%; v i/ w;

Httvrnex Patented Nov. 13, 1923.

NE- TATES tease areur earl PA UL SLESAZECK, OF BERLIN-REINICKENDORF,GERMANY.

Application filed ril 15,

To aZZ whom it may concern.

Be it known that I, PAUL SLESAZECK, a citizen of'the German Republic,and a resident of 'Berlin-Reinickendorf, Germany, have invented certainnew and useful Improvements in Expanding Devices for Boiler Tubes andthe like, of which the following is a specification.

This invention relates to a device for ex- 'panding boiler tubesandsimilar tubes in the walls of boilers, which permits of securingthe-tubes conveniently and rapidly in a fluid tight manner. In expandingdevices at present in use the mandrel, which is adapted to press theexpanding rollers radially outwards, is advanced from time to time by anut. This causes the disadvantage, that the rollers are easily pressedout too far and penetrate into the material too deeply.

The feature of the new invention consists in that the casing of theexpanding device is split resiliently in its longitudinal direction andsurrounds a preferably conical nut with friction, this friction beingpreferably increased by a ring placed around the casing.

In the accompanying drawing Figure 1 shows a section of the casing onthe line A-B of Fig. 3, as also an elevation of the mandrel.

Fig. 2 shows an external view of the expanding device, and Fig. 3 is afront elevation seen from the right, while Fig. 4 represents in externalview an especially advantageously operating modification of my improvedexpanding devlce.

1 is the casing of the expanding device, which at 2 is provided with theopenings, in which the expanding rollers 3 are mounted. 4- is a conicalmandrel, which may be fed forwards by means of a screw thread 5, byturning its part 6 by hand or mechanically. 7 isa nut, which surroundsthe screw-sp1ndle 5, and which externally is provided with a slight cone8. A corresponding recess is provided in the casing 1 for this cone.

The casing is provided with a number of slots 9 in its axial direction,so that spring tongues 11 are formed, which surround the cone 8 with astrong spring action.

The method of operation will now be as.

follows:

If the spindle 5 is turned in a given direction, the mandrel 4 will thusbe advanced towards the left and thus press the expand ing rollers 3radially outwards, so that they expand the tube to be packed. If theexpan- 1a2 2. Serial No. 553,221.

sion pressure is sufficiently great, the conical nut 7 is pressedoutsomewhat towards the right, as the pressure of the spring tongues 11has been overcome. The extent of pro- 00 jection of a few millimetersindicates to the workman that the expansion pressure suffices. It is nowonly necessary for him to turn the spindle 5 in the opposite direction.The nut 7 then returns wholly into the position of Fig. 1, while at thesame time the mandrel 4 moves towards the right so that the expandingrollers also move towards the centralaxis of the casing and theexpanding device can be removed, so as to be inserted into another tube,where the same method of operation is repeated.

For increasing the spring pressure of the tongues 11 a ring 12 may beplaced over the tongues as shown in Figs. 1 and-2, which may also. beresilient. This ring may be moved in an axial direction and the springpower of the tongues thus varied.

It is of advantage to make the ring 12 resilient in order to prevent adeformation of the parts 11 by means of the sharp edges of said ring,when these parts 11 are spread outwardly by the cone 8. The resilienceof the ring 12 is effected by means of a slot 13, ppt longitudinally insaid ring as shown in In the modification shown in Fig. 4 the ring 12 isreplaced by a spiral spring 14, which is pushed with strong tension overthe parts 11 and is adapted to expand radially.

The advantage of the new device consists in a very rapid method ofoperation and further in that it is possible to operate uninterruptedlywithout, as with the older constructions, it being necessary to effect aperiodic feed of the spindle 5. The workman needs only to take care thathe stops the movement for expansion when the ex- 'ternallyconically-shaped nut 7 has the right hand end projected a. fewmillimeters beyond the right hand end of the casing.

Having thus particularly described the nature of my invention, what Iclaim as new and desire to secure by Letters Patent of the United Statesis:

1. A device for expanding heating tubes in boiler walls, comprising incombination a casing resiliently split in its longitudinal direction,'rollers mounted in said casing so as to be radially movable andadapted to be pressed against the tube wall in order to expand the same,a comically-shaped mandrel adapted to engage between said rollers andhaving external screw threads and a nut engaging with said screw threadsand being friction-ally surrounded by said casin 2. A device forexpanding heating tubes in boiler walls, comprising in combination acasing having an'open end resiliently split in its longitudinaldirection, rollers mounted in said casing so as to be radially movableand adapted to be'pressed against the tube wall inorder to expand thesame, a conically-shaped mandrel adapted to engage said rollers andhaving external screw threads and a conically-shaped nut engaging withsaid screw threads and being frictionally surrounded by a cor'espondingly shaped part of said casing, the smaller base surfacethreads, a conically-shaped nut engaging.

with said screw threads, and being frictionally surrounded by acorrespondingly shaped part of said casing, the smaller base surface ofsaid nut being turned towards the open end of the casing and resilientmeans encircling said casing and being adapted to be expanded radially.

4:- A device for expanding heating tubes in boiler walls, comprising incombination a casing having an open end resiliently split in itslongitudinal direction, rollers mounted in said casing so as ,to beradially movable and adapted to be pressed against the tube wall inorder to expand the same, a coni cally-shaped mandrel adapted to engagebetween said rollers and having external screw threads, aconically-shaped nut engaging with said screw threads and beingfrictionally surrounded by a con'espondinglyshaped part of said casing,the smaller base surface of said nut being turned towards the open endof the casing and a spiral spring encircling the resilient end of saidcasing and being adapted to be expanded radially.

In testimony whereof I aiiix my signature in presence of two witnesses.

PAUL SLESAZECK. Witnesses v ARTHUR Aonnonsn,

R. T. HUSPERD.

